Abstract: A polyvinyl alcohol (PVA) microporous membrane is disclosed which is prepared by a process which comprises forming a PVA membrane containing fine silica particles therein and substantially extracting said silica particles from said membrane, thereby forming a plurality of micropores therein with an average diameter of 0.01 to 50 microns and a porosity of at least 60%.

Abstract: A flow regulating device provides continuous, regulated flow of a medical fluid, as well as intermittent, manually controlled larger flows of fluid to a catheter system. Such apparatus includes a control member having an inlet means adapted to be connected by tubing to a source of medical fluid and an outlet means adapted to be connected by tubing to a catheter. A flexible conduit defines at least a portion of a first passage between the inlet means and outlet means of the control member. A cylindrical, hollow extension extends from the outlet means coaxially within and to about the midsection of the flexible conduit. Positioned in the flexible conduit is valve means adapted to open when the conduit is squeezed, thereby providing the larger, intermittent, manually controlled flow of fluid to the catheter system, and to automatically close when the conduit is released.

Abstract: Disclosed is a liquid separation module of the spiral type which is produced by a simple apparatus requiring no manual operations, so that a mandrel is provided with a spirally and tightly wound layer arrangement consisting of a plurality of layer elements without any abnormal relative shifting between any layer elements, without the occurrence of wrinkles in any layer element and with uniform tightness of the winding along the radius of the wound layer arrangement. The layer arrangement is wound on the mandrel in such way that, while the layer arrangement is being wound on the mandrel by rotating the mandrel with the forward end of the layer arrangement fixed to the mandrel, a portion of the layer arrangement which has not yet been tightly wound is radially pressed just before coming into tight contact with the mandrel or with another portion of the layer arrangement which has been tightly wound, so that the degree of winding tightness is increased separated from each other.

Abstract: A low pressure, high flux water purification system. In a continuous loop recirculation system metal hydroxides are employed to bind impurities in wastewater into particles of a size greater than ten angstroms which are then separated from the water by means of an ultrafiltration membrane. A large metal hydroxide/impurity ratio is maintained thereby permitting a purified water flux of over 30 gfd using filter tubes of diameter greater than 100 mils and length greater than 6 inches under a wastewater pressure as low as 9 psig. The filter tubes are grouped in bundles, each bundle within its own water collecting box, so that system down time is minimized and purification standards may be maintained in the event of a partial failure of the system.

Abstract: A multilayer cellulosic membrane for blood dialysis and a method for the production of said membrane by regeneration from separately extruded cuprammonium cellulose solutions brought together to form two or more permanently adhered layers, each layer forming a seal against blood penetration through the leakage points of an adjacent layer, the resulting multilayer membrane thus being substantially free of blood leakage over the total thickness of the membrane. Especially preferred membranes for blood dialysis are those in which the layer arranged on the blood side of the diaphragm contains a modified cellulose chemically bound with an antithrombogenic substance.

Abstract: An improved cellulose acetate semi-permeable hollow fiber suitable for use in artificial kidneys and a process for making same.

Abstract: A regeneratable peritoneal dialysis bag having a hollow fiber filtration bundle affixed to flexible plastic sidewalls so as to regenerate peritoneal fluid within the bag. An orifice in the bag allows for fluid connection with a peritoneal cavity. A method for use of such bag to regenerate peritoneal dialysate is also disclosed.

Abstract: A portable, self contained skimmer utilizes an endless flexible belt which depends into the liquid to be skimmed and is driven between two rollers for removal of liquid from the belt.

Abstract: A dialyzer is formed by first placing a film strip into a membrane hose and then simultaneously folding the hose and a netting intermediate layer so that the folds of the hose and the folds of the netting extend crosswise relative to each other in a mutually interlocking manner. The facing ends of the hose layers are then sealed with a curable sealing compound and severed. Then the film strips are withdrawn from the hoses in the so formed package. The resulting product is a dialyzer or hemofilter, depending on the type of membrane hose used, in which the facing ends of the membrane hoses are open for the passage of blood therethrough, after the withdrawal of the film, and in which the netting layers are located between adjacent hoses.

Abstract: A method for preventing gastro esophageal reflux when the gastro esophageal junction is positioned above the diaphragm. The method comprises positioning a generally C-shaped cushion prosthesis about the distal esophagus, adjusting the free ends of the prosthesis at a spacing to permit normal expansion of the esophagus during swallowing and fixing the free ends of the prosthesis in the adjusted position to maintain the prosthesis in operative position around the distal esophagus adjacent to the gastric fundus when the gastro esophageal junction is positioned above the diaphragm and to maintain the adjusted spacing of the free ends. The inside diameter of the prosthesis generally corresponds to the normal outside diameter of the distal esophagus, and the C-shaped member is deformable to permit adjustment of the spacing of the free ends at a selected distance.

Abstract: A method for maintaining the intra-abdominal reduction of a sliding esophageal hernia. The method comprises positioning a generally C-shaped cushion prosthesis around the distal esophagus between the diaphragm and stomach. The overall size of the prosthesis is large enough to prevent extension of the gastric fundus into the thoracic cavity through an enlarged esophageal hiatus. The prosthesis is of generally constant cross-sectional area along its entire length to prevent upward migration of the prosthesis through the enlarged esophageal hiatus and to maintain the accentuated curvature of the esophagus induced by emplacement of the prosthesis. Tie means are provided to maintain the prosthesis in operative position.

Abstract: Disclosed is a method for recovering acrylic resin from an excess of a sprayed powder coating composition. An excess of the powder coating composition which is not deposited onto an article to be coated and is recovered in a coating apparatus is dissolved in an aromatic hydrocarbon solvent which dissolves the acrylic resin component and which has a solubility of a curing agent of not more than 1.0 g (curing agent)/100 g (solvent) at 20.degree. C. and the acrylic resin component is recovered from the resin solution. The acrylic resin component thus recovered can be reused as a resin component for coating compositions.

Abstract: Dialysis apparatus is arranged to enable convenient measuring of ultrafiltration rate from liquid, such as blood, that is to be dialyzed. Dialyzer can have, downstream of a dialysis chamber, a dialyzate passageway through which the ultrafiltration flow rate can be readily measured as by introducing a gas bubble into the dialyzate and timing its movement through the passageway. An air-injection attachment can be fitted to the dialyzer or to a dialyzate supply system, to inject the gas bubble for such measurement. Bubble injection can also be effected in a flow rate measuring passageway downstream of the dialyzer. Flow rates of dialyzate into and out of dialyzer can be compared to show ultrafiltration while dialyzing. The gas injector can be valve-containing unit also equipped with a paddle-wheel dialyzate flow indicator.

Abstract: Novel thixotropic polyurethane compositions particularly useful as sealants for the edges of folded membrane separatory devices are provided which comprise;(a) a prepolymer comprising the reaction product of a polyol having a hydroxyl functionality of at least 2 with one mole per hydroxy group of said polyol of an organic diisocyanate; and(b) a crosslinking agent comprising a polyether polyol having a hydroxyl functionality of at least 2 and a primary amine-terminated polyether having an amine functionality of at least 2.To accelerate curing of the composition, the crosslinking agent can be modified by employing primary hydroxyl-terminated polyethers and/or adding hydroxyl-containing tertiary amines.

Abstract: In apparatus containing a bundle of tubes such as permeators, a tubular spacer substantially surrounds a tube sheet in which tubes are embedded for at least a portion of the lateral surface of the tube sheet. The tubular spacer serves to position the tube sheet within the apparatus. The tube sheet has at least one rise region intermediate a face and an expanded zone having larger cross-sectional dimensions than the corresponding dimensions of the face, and the rise region is adapted to abut the tubular spacer. The tube sheet can have sufficient length along the orientation of the tubes in order to ensure a fluid tight relationship between tubes and the tube sheet, and the amount of material to form the tube sheet can be reduced, thereby minimizing the effect of differential expansions.

Abstract: Catalysts of various types, preferably enzymes, are immobilized on hollow fiber membranes in novel way to provide a new system for performing catalytic reactions. In preferred embodiments, novel processes for catalyzing reactions utilizing hollow fiber techniques are disclosed.

Abstract: A permselective membrane comprising a thin permselective film of a polymeric material, said polymeric material being prepared by cross-linking a polyaddition product between a polyepoxy compound and a polyamino compound having at least two amino groups capable of reacting with epoxy groups with a polyfunctional compound selected from the group consisting of aromatic, heterocyclic and alicyclic compounds containing at least two functional groups selected from acid halide, sulfonyl halide, isocyanate and acid anhydride groups; and a process for producing the same. The permselective membrane of this invention is especially useful for desalination of saline or brackish water by reverse osmosis.

Abstract: An intermittently operating pressurized filter for concentrating a solid matter suspension, comprising a filtering tank with an inlet conduit provided with a feed pump for introducing under pressure the suspension to be filtered, and a draining conduit provided with valve for removal of the concentrated sludge, and a plurality of filtering elements suspended from the roof, through which the filtrate flows and of which the interior communicates with a filtrate collecting tank located above and which thereby collect on their external surface sludge, which has been arranged to be periodically removed by voiding the pressure within the filtering tank by opening for the suspension therein an exit flow path through a draining conduit. The filtrate in the collecting tank will pass in countercurrent fashion through the filtering elements.

Abstract: An in-line fluid filter of the multi-piece type having a pair of body sections coaxially secured to each other. A filter element is fixedly disposed transversely across a filter chamber defined by the body sections intermediate a fluid filter inlet and outlet. This filter element includes an annular mounting flange interposed between mating annular body section end faces. A generally cup-shaped filter element support is fixedly located on at least the outlet side of the filter element and is dimensioned so that the filter element is at least partially received in the cup-shaped area thereof. This support includes an annular mounting rim which is also interposed between the body section end faces. The support allows the filter to experience greatly increased fluid pressure differentials across the filter element. The filter element mounting flange and the support mounting rim are dimensioned to at least extend to the outside diameter of the mating body section annular end faces.

Abstract: Separation apparatus useful particularly for ultrafiltration in which a series of membranes are mounted in superposed relationship with membrane supports, and, where appropriate, distribution plates therebetween, the membranes being mounted in subassemblies so that the flow of fluid through the individual chambers between the membranes of a particular sub-assembly is substantially in parallel. .Iadd.